<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            /* width: 200px; */

            background-color: pink;
        }

        body {
            height: 100px;
            margin: 0em;
        }
    </style>

</head>

<body>
    <!-- 文字类块级标签不能放其他块级元素 p,h-->
    <div>独占一行</div>
    <div>瑟瑟发抖</div>
</body>

</html>